Re: ldconfig/prebind.c - remove dead assignments
David Hill dh...@mindcry.org writes:
remove unused variables.
Makes sense. ok?
Index: ldconfig/prebind.c
===
RCS file: /cvs/src/libexec/ld.so/ldconfig/prebind.c,v
retrieving revision 1.20
diff -u -p -r1.20 prebind.c
--- ldconfig/prebind.c4 May 2013 09:23:33 - 1.20
+++ ldconfig/prebind.c5 Jul 2013 18:18:24 -
@@ -472,12 +472,10 @@ done:
int
elf_check_note(void *buf, Elf_Phdr *phdr)
{
- Elf_Ehdr *ehdr;
u_long address;
u_int *pint;
char *osname;
- ehdr = (Elf_Ehdr *)buf;
address = phdr-p_offset;
pint = (u_int *)((char *)buf + address);
osname = (char *)buf + address + sizeof(*pint) * 3;
@@ -1712,7 +1710,6 @@ elf_write_lib(struct elf_object *object,
u_int32_t next_start, *fixuptab = NULL;
struct stat ifstat;
off_t base_offset;
- size_t len;
int fd = -1, i;
int readonly = 0;
@@ -1729,7 +1726,7 @@ elf_write_lib(struct elf_object *object,
readonly = 1;
}
lseek(fd, -((off_t)sizeof(struct prebind_footer)), SEEK_END);
- len = read(fd, footer, sizeof(struct prebind_footer));
+ read(fd, footer, sizeof(struct prebind_footer));
if (fstat(fd, ifstat) == -1) {
perror(object-load_name);
@@ -2210,7 +2207,6 @@ void
copy_oldsymcache(int objidx, void *prebind_map)
{
struct prebind_footer *footer;
- struct elf_object *object;
struct elf_object *tobj;
struct symcache_noflag *tcache;
struct symcachetab *symcache;
@@ -2219,8 +2215,6 @@ copy_oldsymcache(int objidx, void *prebi
u_int32_t offset;
u_int32_t *poffset;
struct nameidx *nameidx;
-
- object = objarray[objidx].obj;
poffset = (u_int32_t *)prebind_map;
c = prebind_map;
Re: ldconfig/prebind.c - remove dead assignments
On Sun, Jul 14, 2013 at 09:23:53AM +0200, J??r??mie Courr??ges-Anglas wrote:
David Hill dh...@mindcry.org writes:
remove unused variables.
Makes sense. ok?
Index: ldconfig/prebind.c
===
RCS file: /cvs/src/libexec/ld.so/ldconfig/prebind.c,v
retrieving revision 1.20
diff -u -p -r1.20 prebind.c
--- ldconfig/prebind.c 4 May 2013 09:23:33 - 1.20
+++ ldconfig/prebind.c 5 Jul 2013 18:18:24 -
@@ -472,12 +472,10 @@ done:
int
elf_check_note(void *buf, Elf_Phdr *phdr)
{
- Elf_Ehdr *ehdr;
u_long address;
u_int *pint;
char *osname;
- ehdr = (Elf_Ehdr *)buf;
address = phdr-p_offset;
pint = (u_int *)((char *)buf + address);
osname = (char *)buf + address + sizeof(*pint) * 3;
@@ -1712,7 +1710,6 @@ elf_write_lib(struct elf_object *object,
u_int32_t next_start, *fixuptab = NULL;
struct stat ifstat;
off_t base_offset;
- size_t len;
int fd = -1, i;
int readonly = 0;
@@ -1729,7 +1726,7 @@ elf_write_lib(struct elf_object *object,
readonly = 1;
}
lseek(fd, -((off_t)sizeof(struct prebind_footer)), SEEK_END);
- len = read(fd, footer, sizeof(struct prebind_footer));
+ read(fd, footer, sizeof(struct prebind_footer));
Here I would consider actually using len to check for failure. And of
course changing the type of len to ssize_t to allow such checking.
Ken
if (fstat(fd, ifstat) == -1) {
perror(object-load_name);
@@ -2210,7 +2207,6 @@ void
copy_oldsymcache(int objidx, void *prebind_map)
{
struct prebind_footer *footer;
- struct elf_object *object;
struct elf_object *tobj;
struct symcache_noflag *tcache;
struct symcachetab *symcache;
@@ -2219,8 +2215,6 @@ copy_oldsymcache(int objidx, void *prebi
u_int32_t offset;
u_int32_t *poffset;
struct nameidx *nameidx;
-
- object = objarray[objidx].obj;
poffset = (u_int32_t *)prebind_map;
c = prebind_map;
Re: ldconfig/prebind.c - remove dead assignments
Kenneth R Westerback kwesterb...@rogers.com writes:
On Sun, Jul 14, 2013 at 09:23:53AM +0200, J??r??mie Courr??ges-Anglas wrote:
David Hill dh...@mindcry.org writes:
remove unused variables.
Makes sense. ok?
[...]
lseek(fd, -((off_t)sizeof(struct prebind_footer)), SEEK_END);
- len = read(fd, footer, sizeof(struct prebind_footer));
+ read(fd, footer, sizeof(struct prebind_footer));
Here I would consider actually using len to check for failure. And of
course changing the type of len to ssize_t to allow such checking.
Ken
Sure (assuming that an undetected lseek() error would be caught by
read()).
Index: prebind.c
===
RCS file: /cvs/src/libexec/ld.so/ldconfig/prebind.c,v
retrieving revision 1.21
diff -u -p -r1.21 prebind.c
--- prebind.c 5 Jul 2013 21:10:50 - 1.21
+++ prebind.c 14 Jul 2013 13:04:19 -
@@ -475,12 +475,10 @@ done:
int
elf_check_note(void *buf, Elf_Phdr *phdr)
{
- Elf_Ehdr *ehdr;
u_long address;
u_int *pint;
char *osname;
- ehdr = (Elf_Ehdr *)buf;
address = phdr-p_offset;
pint = (u_int *)((char *)buf + address);
osname = (char *)buf + address + sizeof(*pint) * 3;
@@ -1715,7 +1713,7 @@ elf_write_lib(struct elf_object *object,
u_int32_t next_start, *fixuptab = NULL;
struct stat ifstat;
off_t base_offset;
- size_t len;
+ ssize_t len;
int fd = -1, i;
int readonly = 0;
@@ -1733,6 +1731,11 @@ elf_write_lib(struct elf_object *object,
}
lseek(fd, -((off_t)sizeof(struct prebind_footer)), SEEK_END);
len = read(fd, footer, sizeof(struct prebind_footer));
+ if (len == -1) {
+ perror(object-load_name);
+ close(fd);
+ return 1;
+ }
if (fstat(fd, ifstat) == -1) {
perror(object-load_name);
@@ -2213,7 +2216,6 @@ void
copy_oldsymcache(int objidx, void *prebind_map)
{
struct prebind_footer *footer;
- struct elf_object *object;
struct elf_object *tobj;
struct symcache_noflag *tcache;
struct symcachetab *symcache;
@@ -,8 +2224,6 @@ copy_oldsymcache(int objidx, void *prebi
u_int32_t offset;
u_int32_t *poffset;
struct nameidx *nameidx;
-
- object = objarray[objidx].obj;
poffset = (u_int32_t *)prebind_map;
c = prebind_map;
Re: ldconfig/prebind.c - remove dead assignments
On Sun, Jul 14, 2013 at 03:13:32PM +0200, J??r??mie Courr??ges-Anglas wrote:
Kenneth R Westerback kwesterb...@rogers.com writes:
On Sun, Jul 14, 2013 at 09:23:53AM +0200, J??r??mie Courr??ges-Anglas wrote:
David Hill dh...@mindcry.org writes:
remove unused variables.
Makes sense. ok?
[...]
lseek(fd, -((off_t)sizeof(struct prebind_footer)), SEEK_END);
-len = read(fd, footer, sizeof(struct prebind_footer));
+read(fd, footer, sizeof(struct prebind_footer));
Here I would consider actually using len to check for failure. And of
course changing the type of len to ssize_t to allow such checking.
Ken
Sure (assuming that an undetected lseek() error would be caught by
read()).
I guess lseek() should also have a result check, as the rabbit hole
yawns wider. :-) But to concentrate on the read, I think the other
error to check for is a short read. But not being a ld.so hacker I
have no feel for how much trouble could be caused by only reading
in a partial object. I'm guessing the file would have to be truly
pathological.
Ken
Index: prebind.c
===
RCS file: /cvs/src/libexec/ld.so/ldconfig/prebind.c,v
retrieving revision 1.21
diff -u -p -r1.21 prebind.c
--- prebind.c 5 Jul 2013 21:10:50 - 1.21
+++ prebind.c 14 Jul 2013 13:04:19 -
@@ -475,12 +475,10 @@ done:
int
elf_check_note(void *buf, Elf_Phdr *phdr)
{
- Elf_Ehdr *ehdr;
u_long address;
u_int *pint;
char *osname;
- ehdr = (Elf_Ehdr *)buf;
address = phdr-p_offset;
pint = (u_int *)((char *)buf + address);
osname = (char *)buf + address + sizeof(*pint) * 3;
@@ -1715,7 +1713,7 @@ elf_write_lib(struct elf_object *object,
u_int32_t next_start, *fixuptab = NULL;
struct stat ifstat;
off_t base_offset;
- size_t len;
+ ssize_t len;
int fd = -1, i;
int readonly = 0;
@@ -1733,6 +1731,11 @@ elf_write_lib(struct elf_object *object,
}
lseek(fd, -((off_t)sizeof(struct prebind_footer)), SEEK_END);
len = read(fd, footer, sizeof(struct prebind_footer));
+ if (len == -1) {
+ perror(object-load_name);
+ close(fd);
+ return 1;
+ }
if (fstat(fd, ifstat) == -1) {
perror(object-load_name);
@@ -2213,7 +2216,6 @@ void
copy_oldsymcache(int objidx, void *prebind_map)
{
struct prebind_footer *footer;
- struct elf_object *object;
struct elf_object *tobj;
struct symcache_noflag *tcache;
struct symcachetab *symcache;
@@ -,8 +2224,6 @@ copy_oldsymcache(int objidx, void *prebi
u_int32_t offset;
u_int32_t *poffset;
struct nameidx *nameidx;
-
- object = objarray[objidx].obj;
poffset = (u_int32_t *)prebind_map;
c = prebind_map;
Re: ldconfig/prebind.c - remove dead assignments
On Sun, Jul 14, 2013 at 05:56:46PM +0200, J??r??mie Courr??ges-Anglas wrote:
Kenneth R Westerback kwesterb...@rogers.com writes:
On Sun, Jul 14, 2013 at 03:13:32PM +0200, J??r??mie Courr??ges-Anglas wrote:
Kenneth R Westerback kwesterb...@rogers.com writes:
On Sun, Jul 14, 2013 at 09:23:53AM +0200, J??r??mie Courr??ges-Anglas
wrote:
David Hill dh...@mindcry.org writes:
remove unused variables.
Makes sense. ok?
[...]
lseek(fd, -((off_t)sizeof(struct prebind_footer)), SEEK_END);
- len = read(fd, footer, sizeof(struct prebind_footer));
+ read(fd, footer, sizeof(struct prebind_footer));
Here I would consider actually using len to check for failure. And of
course changing the type of len to ssize_t to allow such checking.
Ken
Sure (assuming that an undetected lseek() error would be caught by
read()).
I guess lseek() should also have a result check, as the rabbit hole
yawns wider. :-)
So let's do that.
But to concentrate on the read, I think the other
error to check for is a short read. But not being a ld.so hacker I
have no feel for how much trouble could be caused by only reading
in a partial object. I'm guessing the file would have to be truly
pathological.
I wondered about that case too, but got lazy. Turns out footer is 80
bytes, while black box testing shows that this code path isn't hit
for files invalid - not looking like ELF enough or smaller than 475
bytes (on my i386 machine).
In any case, I don't think a check hurts much.
(elf_sum_reloc() ansified while here, must stop adding stuff over diffs...)
Index: prebind.c
===
RCS file: /cvs/src/libexec/ld.so/ldconfig/prebind.c,v
retrieving revision 1.21
diff -u -p -p -u -r1.21 prebind.c
--- prebind.c 5 Jul 2013 21:10:50 - 1.21
+++ prebind.c 14 Jul 2013 15:50:24 -
@@ -152,7 +152,7 @@ struct elf_object * elf_lookup_object_de
void elf_free_curbin_list(struct elf_object *obj);
void elf_resolve_curbin(void);
struct proglist *elf_newbin(void);
-void elf_sum_reloc();
+void elf_sum_reloc(void);
int elf_prep_lib_prebind(struct elf_object *object);
int elf_prep_bin_prebind(struct proglist *pl);
void add_fixup_prog(struct elf_object *prog, struct elf_object *obj, int idx,
@@ -475,12 +475,10 @@ done:
int
elf_check_note(void *buf, Elf_Phdr *phdr)
{
- Elf_Ehdr *ehdr;
u_long address;
u_int *pint;
char *osname;
- ehdr = (Elf_Ehdr *)buf;
address = phdr-p_offset;
pint = (u_int *)((char *)buf + address);
osname = (char *)buf + address + sizeof(*pint) * 3;
@@ -1425,7 +1423,7 @@ elf_init_objarray(void)
}
void
-elf_sum_reloc()
+elf_sum_reloc(void)
{
int numobjs;
int err = 0;
@@ -1715,7 +1713,7 @@ elf_write_lib(struct elf_object *object,
u_int32_t next_start, *fixuptab = NULL;
struct stat ifstat;
off_t base_offset;
- size_t len;
+ ssize_t len;
int fd = -1, i;
int readonly = 0;
@@ -1731,8 +1729,24 @@ elf_write_lib(struct elf_object *object,
}
readonly = 1;
}
- lseek(fd, -((off_t)sizeof(struct prebind_footer)), SEEK_END);
+ if (lseek(fd, -((off_t)sizeof(struct prebind_footer)), SEEK_END)
+ == -1) {
+ perror(object-load_name);
+ close(fd);
+ return 1;
+ }
+
len = read(fd, footer, sizeof(struct prebind_footer));
+ if (len = -1 len sizeof(struct prebind_footer)) {
I think this condition is incorrect.
if (len == -1 || len sizeof())
perhaps?
Ken
+ close(fd);
+ if (len == -1)
+ perror(object-load_name);
+ else
+ /* paranoia */
+ warnx(%s on %s: short read (corrupted file?),
+ __func__, object-load_name);
+ return 1;
+ }
if (fstat(fd, ifstat) == -1) {
perror(object-load_name);
@@ -2213,7 +2227,6 @@ void
copy_oldsymcache(int objidx, void *prebind_map)
{
struct prebind_footer *footer;
- struct elf_object *object;
struct elf_object *tobj;
struct symcache_noflag *tcache;
struct symcachetab *symcache;
@@ -,8 +2235,6 @@ copy_oldsymcache(int objidx, void *prebi
u_int32_t offset;
u_int32_t *poffset;
struct nameidx *nameidx;
-
- object = objarray[objidx].obj;
poffset = (u_int32_t *)prebind_map;
c = prebind_map;
Re: ldconfig/prebind.c - remove dead assignments
Kenneth R Westerback kwesterb...@rogers.com writes:
On Sun, Jul 14, 2013 at 05:56:46PM +0200, J??r??mie Courr??ges-Anglas wrote:
Kenneth R Westerback kwesterb...@rogers.com writes:
On Sun, Jul 14, 2013 at 03:13:32PM +0200, J??r??mie Courr??ges-Anglas
wrote:
Kenneth R Westerback kwesterb...@rogers.com writes:
On Sun, Jul 14, 2013 at 09:23:53AM +0200, J??r??mie Courr??ges-Anglas
wrote:
David Hill dh...@mindcry.org writes:
remove unused variables.
Makes sense. ok?
[...]
lseek(fd, -((off_t)sizeof(struct prebind_footer)), SEEK_END);
-len = read(fd, footer, sizeof(struct prebind_footer));
+read(fd, footer, sizeof(struct prebind_footer));
Here I would consider actually using len to check for failure. And of
course changing the type of len to ssize_t to allow such checking.
Ken
Sure (assuming that an undetected lseek() error would be caught by
read()).
I guess lseek() should also have a result check, as the rabbit hole
yawns wider. :-)
So let's do that.
But to concentrate on the read, I think the other
error to check for is a short read. But not being a ld.so hacker I
have no feel for how much trouble could be caused by only reading
in a partial object. I'm guessing the file would have to be truly
pathological.
I wondered about that case too, but got lazy. Turns out footer is 80
bytes, while black box testing shows that this code path isn't hit
for files invalid - not looking like ELF enough or smaller than 475
bytes (on my i386 machine).
Hmm, I should have added that feeding it a valid executable truncated to
475 bytes or more produces reproducible segfaults. O:)
In any case, I don't think a check hurts much.
(elf_sum_reloc() ansified while here, must stop adding stuff over diffs...)
Index: prebind.c
===
RCS file: /cvs/src/libexec/ld.so/ldconfig/prebind.c,v
retrieving revision 1.21
diff -u -p -p -u -r1.21 prebind.c
--- prebind.c5 Jul 2013 21:10:50 - 1.21
+++ prebind.c14 Jul 2013 15:50:24 -
@@ -152,7 +152,7 @@ struct elf_object * elf_lookup_object_de
voidelf_free_curbin_list(struct elf_object *obj);
voidelf_resolve_curbin(void);
struct proglist *elf_newbin(void);
-voidelf_sum_reloc();
+voidelf_sum_reloc(void);
int elf_prep_lib_prebind(struct elf_object *object);
int elf_prep_bin_prebind(struct proglist *pl);
voidadd_fixup_prog(struct elf_object *prog, struct elf_object *obj,
int idx,
@@ -475,12 +475,10 @@ done:
int
elf_check_note(void *buf, Elf_Phdr *phdr)
{
-Elf_Ehdr *ehdr;
u_long address;
u_int *pint;
char *osname;
-ehdr = (Elf_Ehdr *)buf;
address = phdr-p_offset;
pint = (u_int *)((char *)buf + address);
osname = (char *)buf + address + sizeof(*pint) * 3;
@@ -1425,7 +1423,7 @@ elf_init_objarray(void)
}
void
-elf_sum_reloc()
+elf_sum_reloc(void)
{
int numobjs;
int err = 0;
@@ -1715,7 +1713,7 @@ elf_write_lib(struct elf_object *object,
u_int32_t next_start, *fixuptab = NULL;
struct stat ifstat;
off_t base_offset;
-size_t len;
+ssize_t len;
int fd = -1, i;
int readonly = 0;
@@ -1731,8 +1729,24 @@ elf_write_lib(struct elf_object *object,
}
readonly = 1;
}
-lseek(fd, -((off_t)sizeof(struct prebind_footer)), SEEK_END);
+if (lseek(fd, -((off_t)sizeof(struct prebind_footer)), SEEK_END)
+== -1) {
+perror(object-load_name);
+close(fd);
+return 1;
+}
+
len = read(fd, footer, sizeof(struct prebind_footer));
+if (len = -1 len sizeof(struct prebind_footer)) {
I think this condition is incorrect.
It checks whether len is in the [-1; 80] range. I was perhaps a bit too
paranoid about the fact that read(2) can return a value between
SSIZE_MAX and SIZE_MAX -2 (see CAVEATS). Since I've read this section
I kinda wired it into my brain; I don't even know if that applies to
OpenBSD.
if (len == -1 || len sizeof())
Of course here the maximum (and desired) return value is 80 so we won't
hit that problem. Maybe a clearer check would be:
if (len != sizeof()) {
if (len == -1)
/* handle error */
else
/* handle short read */
}
which I find clearer.
Does this look reasonable?
Index: prebind.c
===
RCS file: /cvs/src/libexec/ld.so/ldconfig/prebind.c,v
retrieving revision 1.21
diff -u -p -p -u -r1.21 prebind.c
--- prebind.c 5 Jul 2013 21:10:50 - 1.21
+++ prebind.c 14 Jul 2013 18:18:53 -
@@ -152,7 +152,7 @@ struct elf_object * elf_lookup_object_de
void elf_free_curbin_list(struct elf_object *obj);
void elf_resolve_curbin(void);
struct proglist *elf_newbin(void);
-void elf_sum_reloc();
Re: ldconfig/prebind.c - remove dead assignments
j...@wxcvbn.org (Jérémie Courrèges-Anglas) writes:
[...]
len = read(fd, footer, sizeof(struct prebind_footer));
+ if (len = -1 len sizeof(struct prebind_footer)) {
I think this condition is incorrect.
It checks whether len is in the [-1; 80] range.
Err, [-1; 79] (inclusive). No idea about the correct math
representation in other countries.
--
Jérémie Courrèges-Anglas
PGP Key fingerprint: 61DB D9A0 00A4 67CF 2A90 8961 6191 8FBF 06A1 1494
Re: ldconfig/prebind.c - remove dead assignments
On Sun, Jul 14, 2013 at 08:22:45PM +0200, J??r??mie Courr??ges-Anglas wrote:
Kenneth R Westerback kwesterb...@rogers.com writes:
On Sun, Jul 14, 2013 at 05:56:46PM +0200, J??r??mie Courr??ges-Anglas wrote:
Kenneth R Westerback kwesterb...@rogers.com writes:
On Sun, Jul 14, 2013 at 03:13:32PM +0200, J??r??mie Courr??ges-Anglas
wrote:
Kenneth R Westerback kwesterb...@rogers.com writes:
On Sun, Jul 14, 2013 at 09:23:53AM +0200, J??r??mie Courr??ges-Anglas
wrote:
David Hill dh...@mindcry.org writes:
remove unused variables.
Makes sense. ok?
[...]
lseek(fd, -((off_t)sizeof(struct prebind_footer)), SEEK_END);
- len = read(fd, footer, sizeof(struct prebind_footer));
+ read(fd, footer, sizeof(struct prebind_footer));
Here I would consider actually using len to check for failure. And of
course changing the type of len to ssize_t to allow such checking.
Ken
Sure (assuming that an undetected lseek() error would be caught by
read()).
I guess lseek() should also have a result check, as the rabbit hole
yawns wider. :-)
So let's do that.
But to concentrate on the read, I think the other
error to check for is a short read. But not being a ld.so hacker I
have no feel for how much trouble could be caused by only reading
in a partial object. I'm guessing the file would have to be truly
pathological.
I wondered about that case too, but got lazy. Turns out footer is 80
bytes, while black box testing shows that this code path isn't hit
for files invalid - not looking like ELF enough or smaller than 475
bytes (on my i386 machine).
Hmm, I should have added that feeding it a valid executable truncated to
475 bytes or more produces reproducible segfaults. O:)
In any case, I don't think a check hurts much.
(elf_sum_reloc() ansified while here, must stop adding stuff over diffs...)
Index: prebind.c
===
RCS file: /cvs/src/libexec/ld.so/ldconfig/prebind.c,v
retrieving revision 1.21
diff -u -p -p -u -r1.21 prebind.c
--- prebind.c 5 Jul 2013 21:10:50 - 1.21
+++ prebind.c 14 Jul 2013 15:50:24 -
@@ -152,7 +152,7 @@ struct elf_object * elf_lookup_object_de
void elf_free_curbin_list(struct elf_object *obj);
void elf_resolve_curbin(void);
struct proglist *elf_newbin(void);
-void elf_sum_reloc();
+void elf_sum_reloc(void);
int elf_prep_lib_prebind(struct elf_object *object);
int elf_prep_bin_prebind(struct proglist *pl);
void add_fixup_prog(struct elf_object *prog, struct elf_object *obj,
int idx,
@@ -475,12 +475,10 @@ done:
int
elf_check_note(void *buf, Elf_Phdr *phdr)
{
- Elf_Ehdr *ehdr;
u_long address;
u_int *pint;
char *osname;
- ehdr = (Elf_Ehdr *)buf;
address = phdr-p_offset;
pint = (u_int *)((char *)buf + address);
osname = (char *)buf + address + sizeof(*pint) * 3;
@@ -1425,7 +1423,7 @@ elf_init_objarray(void)
}
void
-elf_sum_reloc()
+elf_sum_reloc(void)
{
int numobjs;
int err = 0;
@@ -1715,7 +1713,7 @@ elf_write_lib(struct elf_object *object,
u_int32_t next_start, *fixuptab = NULL;
struct stat ifstat;
off_t base_offset;
- size_t len;
+ ssize_t len;
int fd = -1, i;
int readonly = 0;
@@ -1731,8 +1729,24 @@ elf_write_lib(struct elf_object *object,
}
readonly = 1;
}
- lseek(fd, -((off_t)sizeof(struct prebind_footer)), SEEK_END);
+ if (lseek(fd, -((off_t)sizeof(struct prebind_footer)), SEEK_END)
+ == -1) {
+ perror(object-load_name);
+ close(fd);
+ return 1;
+ }
+
len = read(fd, footer, sizeof(struct prebind_footer));
+ if (len = -1 len sizeof(struct prebind_footer)) {
I think this condition is incorrect.
It checks whether len is in the [-1; 80] range. I was perhaps a bit too
paranoid about the fact that read(2) can return a value between
SSIZE_MAX and SIZE_MAX -2 (see CAVEATS). Since I've read this section
I kinda wired it into my brain; I don't even know if that applies to
OpenBSD.
if (len == -1 || len sizeof())
Of course here the maximum (and desired) return value is 80 so we won't
hit that problem. Maybe a clearer check would be:
if (len != sizeof()) {
if (len == -1)
/* handle error */
else
/* handle short read */
}
which I find clearer.
Does this look reasonable?
Works for me. ok krw@
Ken
Index: prebind.c
===
RCS file: /cvs/src/libexec/ld.so/ldconfig/prebind.c,v
retrieving revision 1.21
diff -u -p -p -u -r1.21 prebind.c
--- prebind.c 5 Jul 2013 21:10:50 - 1.21
+++ prebind.c 14 Jul 2013 18:18:53 -
@@ -152,7 +152,7 @@ struct
ldconfig/prebind.c - remove dead assignments
remove unused variables.
Index: ldconfig/prebind.c
===
RCS file: /cvs/src/libexec/ld.so/ldconfig/prebind.c,v
retrieving revision 1.20
diff -u -p -r1.20 prebind.c
--- ldconfig/prebind.c 4 May 2013 09:23:33 - 1.20
+++ ldconfig/prebind.c 5 Jul 2013 18:18:24 -
@@ -472,12 +472,10 @@ done:
int
elf_check_note(void *buf, Elf_Phdr *phdr)
{
- Elf_Ehdr *ehdr;
u_long address;
u_int *pint;
char *osname;
- ehdr = (Elf_Ehdr *)buf;
address = phdr-p_offset;
pint = (u_int *)((char *)buf + address);
osname = (char *)buf + address + sizeof(*pint) * 3;
@@ -1712,7 +1710,6 @@ elf_write_lib(struct elf_object *object,
u_int32_t next_start, *fixuptab = NULL;
struct stat ifstat;
off_t base_offset;
- size_t len;
int fd = -1, i;
int readonly = 0;
@@ -1729,7 +1726,7 @@ elf_write_lib(struct elf_object *object,
readonly = 1;
}
lseek(fd, -((off_t)sizeof(struct prebind_footer)), SEEK_END);
- len = read(fd, footer, sizeof(struct prebind_footer));
+ read(fd, footer, sizeof(struct prebind_footer));
if (fstat(fd, ifstat) == -1) {
perror(object-load_name);
@@ -2210,7 +2207,6 @@ void
copy_oldsymcache(int objidx, void *prebind_map)
{
struct prebind_footer *footer;
- struct elf_object *object;
struct elf_object *tobj;
struct symcache_noflag *tcache;
struct symcachetab *symcache;
@@ -2219,8 +2215,6 @@ copy_oldsymcache(int objidx, void *prebi
u_int32_t offset;
u_int32_t *poffset;
struct nameidx *nameidx;
-
- object = objarray[objidx].obj;
poffset = (u_int32_t *)prebind_map;
c = prebind_map;
